I was considering the topic of Transponders in relation to the ‘Pirates of Drinax’ Campaign.

- What kind of outdated Transponder will the players find in the Harrier? Will they need a new one?
- Say they don't have a working Transponder - what is the reaction, when they get out of jump in a system? I know: Likely dependent on the size of the system, law level, Starport size, and traffic. But in general?
- Can they get like a "Pirates Transponder" that can fake who they are by broadcasting fake IDs? Is such technology common?
- Has the Imperium in 1105 started rolling out the "Signal GK" transponders that eventually will be the downfall of the Imperium?

Considering the mission for the Harrier, I might say the Drinax government, while cleaning the ship up for use, added a variable transponder. I believe the old Corsair commerce raider had VTs as standard.

No matter what, a detected ship with no transponder signal is priority one suspicious and would be dealt with as such. The point of pirates and raiders in not acting like pirates and raiders. 'Fly casual'.

Transponders will be more or less universal in that all races will be able to pick them up and decode what's being 'said' by the transmitting ship. We have that today with transponders on aircraft and ships, regardless of where they are in the world or what flag they are flying.

The Reach is non Imperial space and indeed in many places no persons space at all.
Maybe in the Glorious Empire a ship must have a transponder or get shot at, and ditto in the small part of the 3I, or the Hierate.
But the rest really has no coherent supra planetary authority, so i suspect that all sorts of transponders exist, probably several standards and transponders that work on all or any of them.
Pirates abound, old decaying Empires cling to faded glory, wanna bet which transponder standard the shell of the Drinax Empire requires for inbound ships, and want to guess if anyone still makes them?

That's kinda why I like the Reaches, it *can* be utterly chaotic and ambiguous.

Of course YMMV and in which case treaties bind all the ship building cultures to one universal standard.. just a bit yawnsville for me.

My expectation would be that the major powers each have their own transponder standards -- but all would be compatible. For example, the Imperium, Aslan Hierate, Zhodani, 2000 Worlds, and Hive Federation would each have their own standard transmission frequency bands and signaling systems, but but they would all understand every other system and be able to respond. (The only exception would be Zhodani core expedition ships that set out before awareness of other interstellar entities -- if they started before the Zhodani met others.)

When encountering a foreign transponder, they would respond accordingly -- "Hello Imperial transponder Spin-Efate-6060842. I am Zhodani transponder Tloql-Esalin-8675309. I am an Alta class frontier trader. My presence in Imperial space is under certificate Esalin-1105-1600." It would be sent in both Zhodani and Imperial frequencies and protocols.

In a region without a clear dominant power, transponders would likely use a default protocol based on their homeworld's closest commercial or political affinity. I think it unlikely that pocket empires or single worlds would create their own protocols; the whole point is to be understood by others.

And yes, a privateer would undoubtedly have variable transponders -- but they'd be built to honestly reply to ships belonging to the authority that offered the privateer the letter of marque.